Multicircuit pushbutton switches



y 4, 1967 E. A. JONES ETAL 3,329,792

MULTICIRCUIT PUSHBUTTON SWITCHES Filed Sept. 7, 1966 3 Sheets-Sheet 1 July 4, 1967 E. A. JONES ETAL MULTICIRCUIT PUSHBUTTON SWITCHES 3 Sheets-Sheet 2 Filed Sept.

WWW- fazaardAJaer IITdI/VE) E. A. JONES ETAL MULTICIRCUIT PUSHBUTTON SWITCHES July 4, 1967 5 sheets-Sheet 5 Filed Sept. 7, 1966 IIMMMMVLME, in? R?! w I. 131 J United States Patent 3,329,792 MULTICIRCUIT PUSHBUTTON SWITCHES Edward A. Jones, Sylmar, and Robert C. Carter, Encino, Califi, assignors to Litton Precision Products, Inc, Van Nuys, Calif., a corporation of Delaware Filed Sept. 7, 1966, Ser. No. 577,729 Claims. (Cl. 200167) ABSTRACT OF THE DISCLGSURE The invention comprises a multicircuit pushbutton switch having a plurality of movable spring finger contacts riding in parallel grooves. A plurality of fixed contacts are disposed at various positions along the length of the grooves. Various of the contacts in each array may be the two arrays of contacts slide with respect to each other as actuated by a pushbutton mechanism including a rotary cam. A terminal header is provided to couple to the switch the circuits to be controlled.

This is a continuation in part of our application Ser. No. 444,687, filed Apr. 1, 1965, for Push Button Switch, now abandoned.

This invention relates to electrical switches and, more particularly, to multicontact switch assemblies and pushbutton assemblies incorporated in such switches.

Illuminated pushbutton switching devices are used in the electrical and electronic fields, and in various industrial instruments to provide multicircuit switching and may include indication of the fact of the switching by a lamp incorporated therein. While this specification describes an illuminated switch, the same inventive concepts are equally applicable to a non-illuminated switch.

In accordance with one aspect of the invention, a multicontact electrical switch assembly includes a first and a second set of contact elements adapted for relative backand-forth motion, between two distinct switch positions, of the contact elements of the first set with respect to those of the second set. In each set, the contact elements are spaced apart in a cylindrical configuration and the back-and-forth motion occurs axially of both configurations of contact elements.

In accordance with a second aspect of the invention, a multicontact electrical switch assembly includes a first and a second set of contact elements adapted for relative back-and-forth motion, between two distinct switch positions, of the contact elements of the first set with respect to those of the second set. Different ones of the contact elements of the second set are disposed at diflerent locations along the path of relative motion of the contact element sets, so that at least one contact element of the second set is engaged by a corresponding contact element of the first set in only one of the two distinct switch positions.

In accordance with a third aspect of the invention, an electrical switch assembly having two distinct axial switch positions, as combined with a pushbutton actuating mechanism, the combination being such that alternate changes of switch positions are brought about as a result of se quential pressure applications to the pushbutton. The mechanism includes a rotatable and axially movable cam having an interrupted spiral-shaped cam surface for controlling said operation.

A variety of cam configurations can be used .to provide diiferent switching arrangements where two or three, or even more, distinct switch positions may be achieved. Thus, for more than two positions, each successive pressure application will turn the cam means through oneinterconnected. Electrical circuits are made and broken as 3,329,792 Patented July 4, 1967 third or other fraction of its cycle to position the contact elements at each such fraction of the cycle at different axial positions in order to achieve particular contact switching combinations.

In an illustrative embodiment of the invention, the pushbutton assembly comprises a rotating and axially movable cam with three identical cam surfaces upon which there rides a tripodal cam actuator which is resiliently urged against the cam surfaces. The pushbutton assembly is cooperatively engaged with a contact array comprising a plurality of dependent spring contact fingers extending skirt-like from and below the rim of an insulative supporting disc.

The contact fingers surround a fixed insulative fluted base, into the fl-utes of which are inserted contact elements that are engageable with the dependent contact fingers. The contact elements in the fluted base are of different lengths and are positioned so as to make contact with predetermined ones of the dependent contact fingers in the various distinct switch positions.

The fluted base is fixed in the switch assembly and the contact elements therein are connected with respective external terminal pins in the base for making external plug-in contact with circuit receptacles provided therefor. Alternatively, the base connections may be solder termiilials of various types, contact blades, or socket receptac es.

In the illustrative embodiment of the invention, rotating cam and the movable contact array are positionable to upper or lower positions with respect to the fixed positions of the cam actuator and the fluted base. In each of its two positions, the contact fingers of the contact array make interconnections with various contact elements on the fluted base and a great variety of connection combinations may be obtained. The connections may be mo- ;nentary, push-push, momentary snap types or hold-down ypes.

The actuating mechanism in the illustrative embodiment is such that successive downward pressures upon the pushbutton alternately position the spring finger contact array in its upper or lower position with respect to the fixed contacts in the fluted base so as to provide at least a two-position switching arrangement. The contact array is resiliently urged by a spring to a normally upper position.

It is an object of this invention to provide a pushbutton actuated switch fior making multicircuit interconnections in electrical or electronic systems.

It is another object of this invention to provide a simple switch contact positioning means, actuated by a pushbutton cooperating therewith.

A further object of this invention is to provide a pushbutton actuated -multicircuit switching means comprising a movable spring finger contact array axially positionable by a rotary cam with respect to a contact supporting base, or core, to make predetermined contact intercomlections with the contacts on said core in different axial positions of said spring finger contacts array.

Yet another object of this invention is to provide in a pushbutton actuated multicircuit switch means for sequentially positioning contact arrays within said switch into one or another of a cycle of several contact positions in response to successive actuations of the pushbutton.

These and other objects of the invention will be clearly understood from the following more detailed description taken in conjunction with the accompanying drawings. The embodiment shown is, of course, merely illustrative and is not to be construed as a limitation of the invention, many variations and modifications of which are possible and may be made by those skilled in the art without exceeding the scope and spirit of the appended claims.

In the drawings:

FIGURE 1 is a partially cutaway and partially cross- .sectional view of a switch according to this invention, showing internal components;

FIGURES 2a and 2b are schematic representations of the contacting portions of a switch according to this invention showing two difierent positions thereof;

FIGURE 3 is an exploded View of the components of the switch;

FIGURE 4 is an overall external View of a switch similar to that of FIGURE 1, reduced in size and including a typical socket connector therefor; and

FIGURE 5 is a cross-sectional view of a switch according to this invention, showing in detail the lamp circuit thereof.

Referring now to the figures generally and more particularly to FIGURE 1, a metallic switch housing 16 is shown having a threaded collar 11 at the neck portion 12 thereof for insertion in a panel or other mounting surface 13. The switch housing is held in place in mounting surface 13 by a nut 14. A locating pin 15 is provided in housing 11! which may be positioned in an appropriate recess or hole 16 in panel or mounting surface 13 to receive pin 15 and prevent the switch from rotating in the panel 13.

A plastic insulating cylinder 17 having an upper portion 13 and lower portion 19 fits into casing 10 to insulate the casing from interior components of the switch. It will be appreciated that the upper and lower portions 18 and 19 may be separate rather than integral, if such is desired for convenience of manufacture or assembly. It is desirable to provide means to prevent rotation of upper portion 18 during operation of the pushbutton mechanism as described below. In the illustrative embodiment, such rotation is prevented by an extension of pin 15 which pro trudes inside housing 16 to engage a hold 121 in cylinder 17. On the inner surface 21 of the upper portion 18 of insulating cylinder 17 inwardly projecting axially extending tracks or guides 21 of rectangular cross sections are provided. Two guides 21 may be seen in FIGURE 1 in exaggerated perspective in the cutaway portion of the upper portion 18 of cylinder 17, but there are three such guides 21 in the illustrative embodiment, as shown in FIGURE 3. The lower ends of tracks or guides 21 are bevelled to match the cooperating surfaces of cam 50 as described further below.

Within insulating cylinder 17 is a plunger drive cylinder 22. Drive cylinder 22 has an upper cup 23 and a guide pin 24 of smaller diameter depending therefrom. Cup 23 is slidable within upper portion 18 of insulating cylinder 17 and includes a flange 27 separating pin 24 from cup 23. In the periphery of flange 27 are notches or grooves 25 to accommodate the tracks or guides 21 of the cylindrical upper portion 18 of cylinder 17. There are three grooves 25 although only one is shown in FIGURE 3. Thus, plunger 22 is mounted for aXial sliding motion Within the upper portion 18 of cylinder 17 along the guides 21, but it cannot rotate because notches 25 accommodate the guides or tracks 21.

A cam actuator 28 having three dependent fingers 29 and a central aperture 30 fits over guide pin 24 and abuts flange 27 of plunger 22. Adjacent the fingers 29, three notches 26 are provided in the cam actuator 28, each of the notches accommodating one of the guides 21 to permit axial sliding motion, but prevent rotation of the actuator. Consequently, both drive cylinder 22 and actuator 28 slide up and down along the tracks or guides 21.

A spring 31 fitting over guide pin 24 and bearing with its lower end against the contact assembly described below, presses against cam actuator 28, uring it upward against flange 27 of plunger drive cylinder 22.

A spring finger contact assembly 32 is made up of two discs 33, 34 between which at least one, preferably a number of contact groups 35 are riveted as shown in the cutaway portion 36 (FIGURE 3) of assembly 32. A rivet 39 holds together each of the contact finger array groups 35 with lower disc 3 In the cutaway detail 36 the spring finger contacts are shown as a group 35 of three fingers. It should be clear that any contact combination of two or more fingers such as that designated 35 can be provided for whatever interconnection operation is desired in a switch according to this invention. The detailed operation as described further below will make this clear.

The assembly of upper and lower discs 33, 34 over contact finger array groups 35 is held together by an eyeletbearing arrangement 37 shown as it appears prior to peening over the top 38 thereof in the exploded view of FIG- URE 3. The inner wall of opening 44) through eyelet-bearing 37 is the bearing surface for slidably guiding pin 24.

The base or flange surface 41 of eyelet 37 rests upon spring 42 which fits about the guide pin 24.

A ring-shaped cam 51 sits upon the upper disc 33 of spring finger contact array 32 with pin 24 extending through the cam. Thus, the cam is mounted for rotational motion about the axis of the assembly, when actuated for such motion. In addition, the cam is axially movable between two end positions, and in this axial motion the contact array assembly 32 follows the cam, as both the assembly 32 and the cam are urged upward by spring 42, and moved downward upon actuation of the pushbutton. The cam 59 has three axially extending recesses, or slots, one being shown in FIGURE 3 as 65, which separate three spiral-shaped ramps, such as 66, about the periphery of the cam 5t). As a ring with three axially extending slots 65 would actually fall apart to form three separate pieces, the cam surfaces of cam 50 are supported by an internal, smaller diameter cylinder designated 543a in FIGURES 3 and 5. Of course, the entire cam 50', including inner ring 5%, may be manufactured as one integral unit. The slots 65 with the inner ring 50a form axial recesses or channels which, in operation, alternately accommodate guides or tracks 21 and fingers 29 as explained in detail below.

Ramps 66 constitute cylindrical spiral or helical surfaces, each ramp being divided into two sections by an upward extension sea which terminates in an edge constituting an upwardly shifted section of the spiral ramp, as shown in FIGURE 1. As illustrated, the width of each of the fingers 29 and protrusions 66a is about equal. To assure proper operation, each protrusion 66a is positioned toward the lower end of the ramp which it divides, so that the higher, wider portion, seen near the center in FIGURE 1, is suificiently wide to receive simultaneously, one next to the other, one of the fingers 29 and one of the tracks or guides 21 passing through notches 25 and 26, the guides having been partly omitted in FIGURE 1 for the sake of clarity. The lower continuation of a ramp 66, appearing at the right-hand side of protrusion 66a in FIGURE 1, is illustrated as having about the width of a single finger 29, or one guide 21 since in operation it accommodates only one of them at a time as explained further below.

The slots 65, ramps 66 and ramp protrusions 66a cooperate with the cam actuator fingers 29 of cam actuator 28, and guides 21 in the following manner.

Cam actuator 28 is raised and lowered within upper portion 18 of cylinder 17 by the application of pressure to pushbutton 1% and thereby to plunger 22. As shown in FIGURE 1, pushbutton is in its upper position. Actuator 28 is urged against flange 27 at the bottom of cup 23 by spring 31 which is partially compressed between actuator 28 and contact assembly 32. Thus, actuator 28 is in its upper position as well. Also as shown in FIGURE 1, assembly 32 is in its upper position with respect to fluted base 45 and cam 50, which rides atop assembly 32, is in its upper position. Assembly 32 is urged upward by spring 42 which is partially compressed between assembly 32 and the bottom of annular groove or depression 46 in base 45.

In the illustrated upper position of cam 50, the bevelled lower edges of actuator fingers 29 bear against the uppermost portions of ramps 66, while guides 21 extend downward into slots 65 with their leading vertical or axially extending edges abutting the trailing vertical or axially extending edges of cam 50 at the highest ends of ramps 66 thereby preventing rotation of cam 50 'by the torque resulting from the pressure of fingers 29 on ramps 66. As pushbutton 100 is moved downward by the application of pressure, plunger 22 is depressed and fingers 29 of actuator 28 bear against cam 50 causing it to move downward with respect to guides 21, causing contact assembly to move downward with respect to fluted base 45, and further compressing spring 42. When cam 50 has moved downward to the point where the tops of ramps 66 are below the bevelled lower edges of guides 21, it is able to rotate and does rotate as a result of the torque resulting from the pressure between fingers 29 of actuator 28 and ramps 66. Rotation of actuator 28 is prevented by the engagement of guides 21 with notches 26. Cam 50 rotates through a small angle until the vertical trailing edges of protrusions 66a come into contact with the vertical leading edges of fingers 29. In this position of cam 50, guides 21 are located above the uppermost portions of ramps 66 where, in the initially described configuration shown in FIGURE 1, fingers 29 were previously stationed.

If the pressure upon pushbutton 100 is now released, spring 31 expands, moving plunger 22 and actuator 28 with fingers 29 upward. When the bevelled lower edges of fingers 29 move above the tops of protrusions 6611, cam 50 is again enabled to rotate and does so as a result of the torque produced by ramps 66 hearing upwardly against the bevelled lower edges of guides 21 as cam 50 is urged upward by spring 42. Cam 50 rotates through another small angle until the vertical trailing edges of protrusions 66a come into contact with the vertical leading edges of guides 21. Actuator 28 and plunger 22 continue to move upward under the influence of spring 31 until flange 27 is stopped by an internal ridge 102 at the top of upper portion 18 of cylinder 17, while cam 50 is locked in its lower position with respect to cylinder 17 and assembly 32 is held by cam 50 in its lower position with respect to fluted base 45 as shown in FIGURE 2(b).

If pressure is again applied to pushbutton 100, plunger 22 is depressed, spring 31 is compressed and actuator 28 moves downwardly until the bevelled lower edges of fingers 29 contact the upper edges of protrusions 66a. As plunger 22 continues to move downward, fingers 29 move cam 50 downward with respect to guides 21. When the upper edges of protrusions 66a descend below the bevelled lower edges of guides 21, cam 50 again is enabled to rotate and does so initially as a result of the torque produced by the bevelled lower edges of fingers 29 bearing on the upper edges of protrusions 66a. After cam 50 rotates through an initial small angle, contact between fingers 29 and protrusions 66a ceases and cam 50 moves upwardly under theurging of spring 42 until the lower portions of ramps 66 contact the bevelled lower edges of fingers 29 and a torque is again produced which causes cam 50 to rotate through an additional small angle until fingers 29 drop into slots 65 and rotation is stopped by contact between the verticalleading edges of fingers 29 and the vertical trailing edges of ramps 66. In this configuration, further axial upward movement of cam 50 is prevented by contact between the bevelled lower edges of guides 21 and the lower portions of ramps 66.

If the pressure on pushbutton 100 is now released, plunger 22 and actuator 28 move upward as spring 31 expands. .When the bevelled lower edges of fingers 29 move above the upper edges of ramps 66, cam 50 is again enabled to rotate and does so as a result of the torque produced by the bevelled lower edges of guides 21 bearing on the lower portions of ramps 66. Rotation continues through a small angle until guides 21 drop into slots 65 6 and the vertical leading edges of guides 21 come into contact with the vertical trailing edges of ramps 66. With guides 21 in slots 65, cam 50 is free for axial upward movement which continues under the urging of spring 42 until the upper portions of ramps 66 contact the bevelled lower edges of fingers 29. Cam 50 and assembly 32 are then in their upper positions with respect to cylinder 17 and base 45, and the switch is again in the configuration illustrated in FIGURE 1.

From the foregoing step-by-step recitation of the operation, it will be clear that in the illustrative embodiment every time the pushbutton is pressed down and released again, the electrical contact assembly 32 is switched between one and the other of the two positions 60 and 61 shown in FIGURES 2(a) and 2( b). Each one of the steps of pushing down the button 100 and releasing it causes rotation of cam 50 which may be referred to as idling because the cam, though driven to rotate by cam action, does not drive any other element to rotate with it. The two stable end positions are reached when the guides, or tracks 21 are either accommodated by slots 65 (FIGURE 1 and upper position 61, FIGURE 2(a) or when stopped by protrusions 66a.

When guides 21 are in slots 65 of cam 50, the adjacent ramp portions rest on fingers 29, which then form a stop for further upward motion of the cam, and contact array 32 is in its upper position 61 as shown in FIGURE 2(a).

When guides 21 are against the wider portions of ramps 66 of cam 50, and stopped from further motion by protrusions 66a, contact array 32 is in its lower position 60 as shown in FIGURE 2(b).

As also shown in FIGURE 5, guide pin 24 rests on spring 43 which is inserted in the center aperture 44 of contact base 45.

Spring 42 rests in annular groove 46 in contact base 45. Base 45 carries a protrusion 103 for engagement with a not-ch 104 in the lower edge of cylinder 17 to prevent relative rotation of cylinder 17 and base 45.

The periphery of contact base 45 is fluted as shown at 47, 48, 49, see also FIGURE 3. Within each of the flutes, i.e. axially extending grooves, is a contact member such as those designated 51, 52, 53.

The grouping of fixed contact members 51, 52, 53 can be seen, particularly in FIGURE 2, to have the following arrangement in the flutes: contact member 51 is a short section near the top of base 45; contact member 52 is a full-length contact member; and contact member 53 is a short member near the bottom of its flute in base 45.

Thus, as may be seen in FIGURE 2(b) when contact finger assembly 32 is in a lower position 60, the three fingers 35 on a common connection shown at the lefthand side are in contact only with the contact members 52 and 53in base 45.

When the three fingers 35 are in the upper position 61 is achieved for the three finger common contact grouping 35.

Any number of contact combinations such as those designated 35 may be used in any combination of arrays. For example, if contacts 35 were a two-finger arrangement, or grouping, a single-pole single-throw operation is achieved. With a pair of three-finger groupings 35, double-pole double-throw contact is possible, utilizing two groupings of fixed contact members 51, 52, 53. A variety of other combinations of fingers and fixed contacts on the base 45 may be included. As the number of combinations in the array increases or decreases, so may the diameter of the array 32 and base 45. By adjusting the .relative lengths or positions of contacts 51, 52, 53 switching action before-break or any other desired form.

Contact base 45 is supported on a header assembly 55 having a plurality of pins 56 depending therefrom. There will normally be as many pins 56 on header 55 as there are contact containing flutes, or grooves, in contact base 45, and each pin will be electrically connected to one of the contacts in the flutes or grooves.

A socket receptacle 57, FIGURE 4, is provided :as a separate unit for mounting in a chassis or similar assembly to receive the pins 56 of header 55.

The socket receptacle 57 may be of such configuration as to be insertable into printed circuit boards to make switches according to this invention capable of being assembled in arrays of such switches on plug-in printed circuit board assemblies, Receptacle 57 may also have contacts of the blade type so as to be easily connectable in wiring harness assemblies, or it may have terminal pins such as 58, illustrated in FIGURES 3 and 4.

The operation of the switch according to the invention described herein can be seen to be as follows.

The insulative contact base 45 has fixed metallic contact elements 51, 52, 53 therein within flutes, or grooves, 47, 48, 49 thereof. By wire connections 59, FIGURE 1, contacts 51, 52, 53 are connected to terminal pins 56 in header 55.

The spring finger contact array 32 is movable over base 45. The fingers 35 of array 32 are in the form of a circular comb. The contact fingers 35 in various contact combinations with the contact elements 51, 52, 53 of different lengths in the flutes 47, 48, 49 in base 45 make a set of connections in an upper position 61 and different connections in a lower position 60. For example, in position 61 connection between contact elements 51 and 52 is completed through fingers 35. In position 60, connection between contact elements 52 and 53 is completed through fingers 35.

Spring finger contact array 32 is held in a normally upward position 61 by spring 42 interposed between the bottom 41 of eyelet 37 of assembly 32 and base 45, see FIGURE 5. When the angular position of cam 50 is such that guides 21 are in slots 65 of the cam, array 32 is held in upper position 61.

Momentary contact operation can be achieved by the omission of elements 28, 31 and 50, permitting plunger 22 to drive assembly 32 directly up and down with respect to base 45.

In FIGURES 3 and 5, there is shown a detail view, in partial cross section, of the lamp-operatnig portion of the pushbutton switch according to this invention.

The contact base 45, as described above, is insulative and fixed in the assembly of the switch. A central bore is provided therein at 44 in which the spring 43 is placed. Upon spring 43 the head or flange 81 of a pin 73 is seated. Guide pin 24 is hollow and an insulative sleeve 70 is inserted into the pin 24 so as to insulate pin 24 from elements in the interior thereof. Sleeve 70 has a flange 69 which separates and insulates the bottom 80 of guide pin 24 from the flange 81 of pin 73 within insulative sleeve 70. Lamp circuit spring 72 separates a contact pin 71 having an enlarged end portion 83 from pin 73 and urges pin 71 upwardly away from 73. Spring 72 provides electrical continuity between pins 71 and 73.

As may be seen in FIGURE 5, lamp 74, which has a base or shell 75 and center contact 76 separated from base 75 by insulator 77, is inserted in a retainer 78 and held in place thereby. Within sleeve 23 of plunger 22, lamp retainer 78 is provided with resilient extensions 69 that engage notches such as 62 in plunger cup 23. The pushbutton cover 100 is engaged by retainer 78 also.

Center lamp terminal 76 makes contact through pin 71, 83, spring 72, pin 73 and spring 43 with terminal pin 85 in base 45. The shell terminal 75 of lamp 74 is in electrical contact with plunger cup 23, which in turn is in contact with spring 31 through cam actuator 28 and eyelet 37 which by its flange 41 through outer spring 42 completes the electrical circuit to terminal pin 84. Regarding this description of the lamp circuit, it will be noted that the insulating sleeve 70 with its flange 69, which separates plunger 24 from pins 71 and 73, though shown in FIGURE 3, has been omitted from FIGURE 5. This has been done for the sake of clarity of the drawing and it must be borne in mind that the elements 71, 83, 72, 73 and 81, is accommodated in, or shown in contact with plunger 24 are in reality electrically insulated therefrom.

In other embodiments of the invention, lamp circuit terminals 84, may be connected through some of the pin terminals 56 to external power connections 50 as to be energized upon the occurrence of one or the other of the positions of contact array 32 (position 60 or 61) to complete the power circuit to lamp 7 4, lighting the lamp for the desired indicating function. The circuit arrangements may include a break in the lamp circuit wherein pin 24 can be made to move to close the circuit at center contact 76 so that lamp 74 lights only when pressure is applied to pushbutton 100.

What is claimed is:

1. An electrical switch comprising:

a base member having a plurality of longitudinally extending parallel grooves;

a plurality of electrical contact elements disposed in said grooves, at least one of said contacts electrically insulated from the others and at least one of said insulated contacts extending over less than the full length of said grooves;

an array of spring finger electrical contact elements having a plurality of fingers positioned in the grooves of said base member and longitudinally movable therein for making electrical contact with selected ones of said plurality of contact elements in predetermined longitudinal positions of said fingers with respect to said grooves.

2. An electrical switch as claimed in claim 1 wherein said base member is insulative.

3. An electrical switch as claimed in claim 1 wherein said base member is cylindrical.

4. An electrical switch as claimed in claim 3 wherein said grooves extend axially of said base member and are disposed about its periphery.

5. An electrical switch as claimed in claim 1 wherein said base member is :an insulative cylinder.

6. An electrical switch as in claim 1 wherein the electrical contact elements disposed in said grooves are of various lengths.

7. An electrical switch as in claim 1 wherein the electrical contact elements disposed in said grooves are at various longitudinal locations with respect to said base member.

'8. An electrical switch as claimed in claim 1 and further comprising means for moving said array between first and second predetermined longitudinal positions with respect to said base member.

9. An electrical switch as claimed in claim 1 wherein selected ones of said spring finger contact elements are electrcially interconnected.

10. An electrical switch as claimed in claim 4 wherein said array of spring finger contact elements is cylindrical and is coaxial with said base and axially movable with respect thereto.

11. An electrical switch as claimed in claim 1 wherein said base member comprises a terminal connection header having a plurality of terminal pins therein, particular ones of the contact elements in said grooves electrically connected to particular one of said terminal pins.

12. An electrical switch as claimed in claim 8 wherein said means for moving said array comprises pushbutton means, a rotary cam mounted for axial motion along its axis of rotation and engaging said array, means engaging said pushbutton means and engageable with said rotary cam for actuating said cam to axial and rotational motion, the axial motion of said cam producing a corresponding longitudinal motion of said spring finger contact elements in said grooves.

13. An electrical switch as claimed in claim 12 and including means for locking said rotary cam in first and second axial stations corresponding to said first and second longitudinal positions when said cam is in first and second rotary positions respectively with respect to said pushbutton engaging means.

14. A pushbutton switch comprising:

a fixed cylindrical array of contacts;

a movable switching means having an array of dependent spring finger contacts mounted for axial movement to first and second axial positions with respect to said fixed array, different sets of contacts of said fixed and movable arrays in electrical contact in said first and second axial positions, selected contacts of said movable array electrically interconnected to provide predetermined connections between cOntacts of said fixed array in said first and second axial positions;

pushbutton means; and

rotary cam means engaging said pushbutton means and including means engaging said movable switching means and adapted to selectively position said spring finger contacts in said first and second axial positions upon successive operations of said pushbutton means.

15. An electrical switch as claimed in claim 14 and further including terminal connection header means having a plurality of terminal pins therein, particular ones of the contacts of said fixed array electrically connected to particular ones of said terminal pins.

References Cited UNITED STATES PATENTS 6/1939 Curtiss 200-l6 11/1965 Miller et al 335126 

1. AN ELECTRICAL SWITCH COMPRISING: A BASE MEMBER HAVING A PLURALITY OF LONGITUDINALLY EXTENDING PARALLEL GROOVES; A PLURALITY OF ELECTRICAL CONTACT ELEMENTS DISPOSED IN SAID GROOVES, AT LEAST ONE OF SAID CONTACTS ELECTRICALLY INSULATED FROM THE OTHERS AND AT LEAST ONE OF SAID INSULATED CONTACTS EXTENDING OVER LESS THAN THE FULL LENGTH OF SAID GROOVES; AN ARRAY OF SPRING FINGER ELECTRICAL CONTACT ELEMENTS HAVING A PLURALITY OF FINGERS POSITIONED IN THE GROOVES OF SAID BASE MEMBER AND LONGITUDINALLY MOVABLE THEREIN FOR MAKING ELECTRICAL CONTACT WITH SELECTED ONES OF SAID PLURALITY OF CONTACT ELEMENTS IN PREDETERMINED LONGITUDINAL POSITIONS OF SAID FINGERS WITH RESPECT TO SAID GROOVES. 